<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			*{
				margin: 0;
				padding: 0;
			}
		/* 	div{
				width: 200px;
				height: 2000px;
				border: 1px solid #000;
				background: url('百度/images/response.png') no-repeat 0 0 ;
				background-size: contain;
				background-attachment: fixed;
				
				
			} */
			
			
			div{
				width: 100px;
				height: 100px;
				
			}
			.box1{
				background-color: red;
			}
			.box2{
				background-color: blue;
				position: fixed;
			}
			.box3{
				background-color: green;
			}
			.box4{
				height: 2000px;
				background-color: yellow;
			}
		</style>
	</head>
	<body>
		
		
	<!-- <div></div>	 -->
		
		
		
		<!-- 
		1.注意点：
		 固定定位的元素是脱离标准文档流的 不会占用位置
		 固定定位和绝对定位一样 不区分行内 行内块 块级元素
		 
		 
		 
		 -->
		 <div class="box1"></div>
		 <div class="box2"></div>
		 <div class="box3"></div>
		
		<div class="box4"></div>
		
	</body>
</html>